According to wikipedia:

A confidence band is used in statistical analysis to represent the uncertainty in an estimate of a curve or function based on limited or noisy data.


Data Analysis videos shared this YouTube video:

And Andy Kriebel shared this one:

Blog posts

Andy also accompanied his video with a blog post:

The Online Tableau Help resource gives an overview of all the Analytics tools here:

And shared a concise overview of Tableau reference lines and bands:

Interworks posed a similar blog post:

Example workbooks

The workbook from Andy Kriebel’s blog is available on Tableau Public here:

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